The present invention relates to a manual device for transferring a film of, for example, an adhesive, a covering, or a colored material from a supporting strip to a substrate. More particularly, the present invention relates to an improved manner by which wheels supplying and taking up the supporting strip may be movably coupled together to mutually transmit movement therebetween.
A manual device for transferring a film from a supporting strip to a substrate is known, for example, from DE-C2-42 20 712 filed by the Applicants, in which a supply wheel and a take-up wheel are in direct frictional contact with each other. The drive connection and slip coupling are formed as one piece by small and simple structural parts so that no additional parts for the drive connection and slip coupling are required and a simple and inexpensive production is achieved.
The wheels of the manual device illustrated in DE-C2-42 20 712 have in each case a hub part from which project lateral wheel walls in the form of round discs, between which the supporting strip is taken up and wound. The drive connection together with the integrated slip coupling is formed by at least one pair of frictional surfaces engaging directly with each other, which surfaces are formed on mutually opposite inner and outer sides of the disc-shaped wheel walls. In order to ensure the rotational drive between the wheels by virtue of the friction acting on the frictional surfaces, a compression stress is required in order to force the frictional surfaces against each other. Alternatively the frictional pressure can also be generated if at least one of the two frictional surfaces is elastically prestressed in the transverse direction and forced against the other frictional surface.
In addition, DE-U1-94 07 305 discloses a manual device for transferring a film from a supporting strip to a substrate in which the drive connection between the supply wheel and the take-up wheel is formed by a friction wheel element arranged in the radial direction flexibly and coaxially relative to the take-up wheel. The friction wheel element rests via a wheel circumferential outer surface against a circumferential surface section of a counter-wheel arranged coaxially relative to the supply wheel in order to generate a frictional force transfer and application region. This manual device is intended to permit in a simple manner the maintenance of an optimum supporting strip tension in very narrow tolerance ranges.
In accordance with the principles of the present invention, an improved drive connection as well as an integrated slip coupling of a manual device for transferring a film from a supporting strip or tape carrier to a substrate are provided. For the sake of simplicity, the combination of film and tape carrier is referenced herein as xe2x80x9ctapexe2x80x9d and the device, as a whole, is referenced herein as a xe2x80x9ctape applicator.xe2x80x9d
In particular, each of the supply wheel and the take-up wheel has a wheel wall. The wheel wall of one of the wheels (e.g., the take-up wheel) is clamped in a slit in the wheel wall of the other wheel (e.g., the supply wheel). Thus, a uniform transfer of torque between the two wheels is ensured at all times. In the drive connection formed according to the present invention together with the integrated slip coupling, no pretensioning in particular is necessary in order to ensure the frictional contact between the supply and take-up wheels.
In a further embodiment of the present invention, the supply wheel, take-up wheel and application device may be integrated in a cartridge that can be inserted into a housing preferably via a corresponding insertion opening in the housing.
The take-up wheel and/or the supply wheel may have a tensioning device for tensioning the tape carrier or tape. In addition, the take-up wheel may be provided with a reverse lock in order to prevent rotation of the take-up wheel in a direction causing unwinding of the tape carrier from the take-up wheel.